It has been the unfortunate province of the stranded or endangered individual to have no system whereby communication could be conducted between the stranded or endangered individual and passing individuals. For instance, in the field of motor vehicles, help is only rendered when a passing vehicle stops and inquires if assistance can be given. However, it may not always be convenient for a passing motorist to stop for safety and other reasons. Similarly, in circumstances where an individual may believe their life is in danger, either from an immediate risk, i.e., personal attack, or imminent risk, i.e., onset of an asthma attack, there are no devices or systems which provide for convenient portable emergency communications.
In order to alleviate this unfortunate lack of communicating capacity in the automotive field, it has been proposed in U.S. Pat. Nos. 3,629,821 and 3,493,924, that a visual motorist aid device be provided whereby passing vehicles could effectively communicate with the stranded motorist.
While the prior art has attempted to solve this communication problem, the solutions posed have been less than optimal. Firstly, the solution posed in U.S. Pat. No. 3,629,821 lacks any means for communicating the nature of the help needed by the individual. For instance, in the circumstance where an individual requires medical assistance, the prior art communication system offered no method of signaling this particular and possibly critical need. Rather, the passing individual could only presume the nature of the assistance needed and stop at the nearest auto servicing or police center to send help to the stranded individual. If the stranded individual required medical help, and there existed some criticality to that need, a shortly arriving tow truck or other service vehicle would be of little help.
The solution posed in the earlier prior art patent, U.S. Pat. No. 3,493,924, offered similar results to the improvement patent previously discussed. The earlier reference did, however, provide an automatic actuation system whereby an impact sensing mechanism would actuate the signalling lights in the event that the automobile operators and passengers of a vehicle equipped with the aid device were unable to manually trigger the signalling system. Similarly, however, the automatic signalling system lacked any provision for indicating the nature of the assistance needed. Rather, the signalling lights would be illuminated which would only indicate a general need for help, again leaving a potential help sender to either speculate about the nature of the help required, or only send mechanical aid.
The prior art systems also lack any provision whereby an unseen vehicle or person requiring assistance could be located by a passing motorist or highway patrolman by other than a visual signalling system. Although the '924 patent discloses that a passing motorist could indicate acknowledgement of having received a distress signal by giving short blasts on the vehicle horn, such an audible signal does little if the passing motorist has not received a distress signal to acknowledge.
Thus, an additional drawback in the prior art is that should a vehicle or person equipped with one of the prior aid devices leave the road or path and be unseen by passing individuals, regardless of the manual or automatic visual signalling taking place, no help of any kind would be sent because passing individuals or patrolmen would remain uninformed as to the need for help.